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Fosbury Flop: Youth Coaching Guidelines
This document has been prepared with the assistance of Gary Bourne and Peter Hannan to provide guidelines for Accredited Athletics Coaches on the appropriate age to introduce the Fosbury Flop to young athletes.
The guidelines are designed to provide a safe training and competition environment that best supports the athletes’ long-term development.
There is currently a lack of consistency across the country on the ideal age to introduce athletes to the Fosbury Flop, which has resulted in some confusion and anxiety between coaches, teachers, parents and administrators. There have been cases of coaches holding a firm coaching philosophy on the best way to map an athlete’s High Jump progression, only to be overruled by a school or parent who have prioritised introducing the flop at an earlier age to prepare young athletes for a junior competition.
It is hoped that this article will be the first step for establishing defined coaching guidelines for when and how to introduce the Fosbury Flop to young athletes and that it will support accredited athletics coaches to follow the most effective longterm strategy for high jump success.
The Appropriate Age to Introduce the Fosbury Flop
It is recommended that athletes begin to learn the Fosbury Flop technique no earlier than 13 years of age.
Any decision about when to introduce the Fosbury Flop technique to a young athlete must be based on the individual athlete’s physical maturity (biological age) and coordination.It is important to remember that a difference of up to two years between a child’s chronological age and their biological age is within the normal range of variation, and differences up to four years have been known. Therefore, some children may have the physical maturity and coordination to commence training at 13 years of age, whereas other children will not possess the same competencies and strength until 15 years or older. The decision about the appropriate age to commence learning the Fosbury Flop should be left to experienced Accredited Coaches and Physical Education Teachers and be based on the individual physical and mental characteristics of the athlete.
In alignment with the Development Model of Sports Participation (Cote, Murphy-Mills & Abernathy, 2007) and the Athletics Coach Education Framework, early specialisation should be avoided. A well-rounded skills and coordination development program that incorporates running, jumping, hurdling, throwing and multi-sport experiences should be the domain of the athlete in the 10 to 15-year-old age group.
Prior to Commencing the Fosbury Flop
Prior to deciding when an athlete is ready to start learning the Flop technique, the focus should be on jumping with the Scissors technique from a straight-line approach to develop the physical attributes required to perform the Fosbury Flop effectively. This should be done in an engaging and enjoyable environment that supports the athlete’s long-term participation in the event.
Transferable jumping skills developed by the Scissors technique include:
• Developing the athlete’s vertical take-off - especiallya strong knee drive and tall posture
• Developing the correct foot plant at take-off (astraight foot plant in line with the run-in)
• Developing a consistent accelerating run upwhere the athlete has the strength and confidence toeffectively ‘attack’ the bar
In developing athletes, the Scissors technique should not be performed from a curved approach as the rotational forces generated on the support leg knee are very high when the swinging leg is in a long,extended position. Without the required strength, the Scissors technique from a curved approach can lead to serious knee injuries.
Attributes of an Athlete Ready to Perform the Fosbury Flop in Training
Prior to attempting the Fosbury Flop in the training environment, the athlete should have developed their Scissors ability and be able to demonstrate the following qualities:
• A consistent approach and take-off position
• A strong knee drive at take-off
• The ability to hold their posture into the flight phase
• The strength to handle the higher physical loads placed on the body and lower limbs
• The confidence and emotional maturity to listen and respond to instructions
Peter Hannan places high value on the importance of the athlete developing the strength to jump through the vertical prior to commencing the Fosbury Flop in training: “Several years ago, I spoke with a highly respected paediatrician, who was also a well- credentialed athletics coach. He said that many parents and coaches were concerned regarding the risk of injuries to the neck from using the Flop technique of high jump. However, he stated that in his experience, he’d seen more people with lower back injuries as a result of a poorly executed flop technique. This was especially prevalent in younger athletes.
The flop technique works because the athlete jumps through the vertical and the centrifugal force from the curve throws them over the bar. However, young kids who aren’t very strong and lack a sufficient vertical jump tend to ‘throw’ their own body over the bar by throwing their lead arm and/or their head over the bar. This results in the lead leg going one way while the upper body goes another way, resulting in large stresses in the lower back.This can be avoided if the athlete has learnt to jump through the vertical by developing their Scissors technique first.…I think everybody, weak or strong,needs to develop the ability to jump through the vertical before performing the Fosbury Flop.”
Signing Off
Prior to introducing the Fosbury Flop in training, it isrecommended that athletes younger than 18 years of age aresigned-off by:
i) An Accredited Athletics Coach AND ii) A physiotherapist or the child’s doctor.
Everybody, weak or strong, needs to develop the ability to jump through the vertical before performing the Fosbury Flop
Attributes of an Athlete Ready to Perform the Fosbury Flop in Competition
The priority for the coach is to ask themselves, “Do I think that this child is going to be in danger of hurting themselves with the technique that they are using?”
Remember that the pressure of competition will exacerbate technical deficiencies as the athlete strains for maximum height.
Level 5 Coaches Peter Hannan and Gary Bourne recommend the following points for the coach to consider when determining whether an athlete is ready to perform the Fosbury Flop in competition:
Consistency: The ability to perform the run-up, take-off, flight and landing phases of the Fosbury Flop consistently in a safe manner.
Foot Plant: Planting the foot at approximately 20 degrees to the bar at take-off. This is essential for ensuring that the optimal takeoff position can be achieved. It also greatly reduces the risk of injury, particularly to the ankle and knee, caused by forces being wrongly directed through those joints.
The final angle of approach (flight path of the final stride) of a Flop High Jumper is between 30-35 degrees to the bar. The change in direction of the Take-off foot plant is approximately 10-12 degrees to the direction of the final stride. This means that the final angle of the foot plant to the bar is around 20 degrees. This angle should point well inside the far upright provided the take-off point is not too far down the bar – a maximum of 50-70cm along from the approach side upright.
Take Off Position Relative to the Bar: The athlete should take off approximately 70cm along the bar. The bar is 4.0m long and the best clearance position is over the middle of the bar, 2.0m from the upright. Ideally, the take-off should be 70cm along and 70-75cm out from the bar with a horizontal velocity of 3.0 – 3.5m/s (half run-up speed), a vertical angle of take-off of 50 degrees and a final angle of flight in relation to the bar of 20 degrees. This will place them close to clearing the centre of the bar.
Achieving the desired take-off position greatly increases the likelihood of the athlete safely clearing the bar. It allows the athlete to maintain a lean away from the bar until foot plant, which assists in generating the required rotation for a successful and safe clearance. This reduces the likelihood of athletes throwing their lead arm or head over the bar to generate unnecessary rotation. Athletes who take off further than one fifth of the length also run the risk of hitting the upright or missing the mat on landing.
Take-off Posture: The athlete’s body should be at right angles to the bar at takeoff, holding a tall posture with their body weight above the planted foot.
Bar Clearance: At the highest point of the athlete’s jump, the line of the athlete’s hips should be parallel to the crossbar, and slightly higher than their knees and shoulders.
Landing: The athlete should be landing at the base of their shoulder blades or at the highest, on their shoulder blades. Landing should be comfortably within the confines of the High Jump mat (to ensure the equipment being used is supporting this outcome, see recommended ‘5 – High Jump Equipment’ for recommended mat dimensions).
It is recommended that the coach should observe the athlete’s ability to perform these six points with consistency before they are ready to use the Fosbury Flop in competition.
Signing Off: Prior to attempting the Fosbury Flop in competition, it is recommended that athletes younger than 18 years of age are signed-off by:
i) Their personal Accredited Athletics Coach using the template included on the full version of this edition of Athletics Coach.
We should teach our young high jumpers NOT to lean back in the final stride as this leads to them placing high loads through their lumbar spine
Injuries Associated with the Fosbury Flop
Accredited Coaches have a responsibility to be aware ofthe risks associated with performing the Fosbury Flop andhow they can contribute to their prevention. Pre-screeningfor existing medical conditions that may affect the athlete’sability to High Jump safely should be conducted prior tocommencing training.
Importance of Supervision by an Accredited Athletics Coach
The presence and active supervision of a qualified coach during training sessions and competition has been found to play an essential role in contributing to injury avoidance for all Track and Field jumps events (D’Souza, 1994). An analysis of injuries that occurred in Track and Field demonstrated that 81.8% of athletes who did not have active coaching supervision suffered an injury over a season,whereas only 40% of those who trained with a qualified coach suffered an injury in the same time-frame.
Gary Bourne on High Jump Injury Prevention: “Paediatrician, the late Dr John Mc.Nee was our Jumps squaddoctor in Brisbane from 1981-2001. In many conversationsI had with him about Flop High Jumping, his strong concernwas the risk of long-term damage to the bones and jointsin the cervical spine (neck region). To this end he publisheda couple of articles expressing his professional concerns tocoaches about children practicing this technique when theneck was not ready to cope with the forces involved. He hadseveral examples of neck injuries sustained by jumpers usingthis technique whilst too young and this has remained aconcern of mine in teaching this event since.
Lower back injuries are undoubtedly a concern, but they emanate from a misunderstanding of technique rather than the Flop technique itself. Lower back injuries tend to be more prevalent in teenage or young adult jumpers as poor technique becomes more of a load issue as they get bigger,heavier and stronger. About two-thirds of the mass of the body is in the region from the hips upward. When a jumper has this part of the body leaning back at touchdown (TD) for takeoff (TO) and they brake at TD (reducing their horizontal velocity by about half), it results in very large forces being transmitted through their lumbar spine. Young jumpers,especially the taller, thinner ones, generally do not have the strength or stability in this part of their body to tolerate these forces (loads) on a regular basis. Consequently, they initially develop a stress reaction (indicated by a sore lower back) and if they keep going, eventually a pars stress fracture of one or more of the lumbar vertebrae - a VERY sore lower back that will see them side-lined from any physical activity for at least 3 months.
To help solve this problem for future generations, we need to do two things. Firstly, we should teach the biomechanically correct preparation for take-off which is to run fast on the curve to ensure the jumper is leaning away from the bar at TD for TO. This ensures they achieve the appropriate lowering of the centre of mass (CM) prior to TD and that the take-off forces will be directed through the CM during the take-off itself. Secondly, we should teach our young high jumpers NOT to lean back in the final stride as this leads to them placing high loads through their lumbar spine during the horizontal braking period and spending too long on the ground during the take-off itself, causing them to lean into the bar at TO. The consequent over-rotation resulting from this technique error causes them to land on the back of their neck and head or high on the shoulders with significant backward somersaulting angular momentum to control at that point.
In short; fix up the curve and the run-in to achieve a goodlean-away, get rid of the lean-back at TD and you will solvethe over-load issue on the lower back as well as reducing therisk to the neck on landing for young athletes. The bonus willbe that they will jump higher due to creating greater impulseduring take-off.”
Common Injuries for Young Jumpers
It is outside of the High Jump coach’s scope of practice to diagnose or treat injuries. However, it is beneficial to understand a little about the more common injuries associated with High Jump to be able to contribute to the prevention of injury and to refer an athlete to a medical professional when they are experiencing symptoms.
The information below is general in nature and is only intended to provide a broad summary of the subject matter covered. It is not a substitute for medical advice and you should always contact a qualifed medical professional.
Overuse Injuries - General Information
Overuse injuries are damage to the body resulting from arepeated action and can affect tendons, cartilage, soft tissue,bone, nerve tissue or muscle-tendon structures.
As you have learnt from the Principles of Training module,training involves the adaptation of the body to stress,strengthening the various tissues involved in the trainingactivity. However, when the training applied is excessiveor the technique being trained is incorrect the desiredadaptation is unable to occur. The excessive overload maycause microscopic injuries, resulting in inflammation toaffected areas.
Overuse injuries develop gradually and follow a commonpattern of progression.
Stage 1: Initial discomfort at the start of training that disappears during the warm up. Stage 2: The pain disappears during warm up but re-appears towards the end of the session. Stage 3: The pain does not go away after the warm up and worsens throughout the activity. Stage 4: Continuous pain that worsens during activity.
By identifying the issue quickly and seeking appropriate medical attention from a trained professional before the injury reaches stage 3 or 4, the coach can help the athlete avoid long-term injuries.
Sever’s Disease (Calcaneal apophysitis)
Description: Inflammation of the growth plate in the heel,usually caused by repetitive stress.
Symptoms: Heel pain that is localised to the posterior and plantar side of the heel. External appearance of the heel is usually normal.
Causes: Overuse of the bone and tendons in the heel that may occur due to over-training or when children are commencing High Jump at the start of a new season or for the very first time. It may also occur as a result of a rapid growth spurt during adolescence.
Prevention: Avoid running on hard surfaces, avoid excessive training load (especially at the start of a new season) and ensure athletes have well-fitting shoes. As prescribed by a health professional, age appropriate foot and leg exercises to stretch and strengthen the leg muscles may also assist prevention and treatment.
Treatment: As directed by a medical professional. Treatment usually focuses on relieving pressure on the heel bone and involves a period of rest between two weeks to two months depending on severity. Check with your Primary Care Physician to check if non-weight bearing exercises, such as swimming, are appropriate during the recovery period.
Jumper’s Knee (patellar tendonitis)
Description: Jumper’s Knee is an overuse injury that results in damage to the patellar tendon. This results in a loss of support or anchoring of the patella, causing pain and weakness in the knee and difficulty straightening the leg.
Symptoms: Knee pain below the kneecap, especially when bending the knee, commonly paired with swelling or tenderness. Stiffness is commonly reported the morning following a training session. Pain may also be experienced in the quadricep or calf muscle.
Coaches should be aware that symptoms may initially be present as very minor, and athletes may decide to ignore the injury and continue training and competing without seeking medical assistance. However, it is important to understand that jumper’s knee is considered a serious condition that can get worse over time and ultimately requires surgical intervention without early medical attention and treatment.
Causes: Jumper’s Knee usually occurs due to a rapid increase in the quantity or intensity of training or insufficient time for recovery between sessions. The tendon is unable to adapt to the training load quickly enough, resulting in greater tissue damage than the body can repair. Dr. Kathleen O’Brien notes that High Jump athletes are at an especially high risk of developing the injury.
Coaches should also be aware that tight quadriceps, hamstring muscles or poor lower limb biomechanics contribute to Jumper’s knee and should refer the athlete to a physiotherapist to correct these issues.
Prevention: Avoiding sudden spikes in training load and ensuring adequate recovery between sessions is the most effective prevention tool. Gentle range-of-motion exercises and stretching to prevent stiffness may also be prescribed by a physiotherapist.
Treatment: It is important that a medical professional evaluates the extent of the injury to prescribe the appropriate treatment. Mild and moderate Jumper’s Knee can be treated through rest, icing, strapping, anti-inflammatory medications and low impact exercises. Surgery is required for more serious injuries.
Osgood-Schlatter’s Disease
Description: A common cause of knee pain in growing adolescents, Osgood-Schlatter’s disease is an inflammation of the growth plate where the patellar tendon attaches to the tibia, known as the tibial tubercle.
Symptoms: Knee pain, swelling and tenderness at the tibial tubercle. The athlete may also experience tight hamstring or quadriceps muscles.
Causes: Osgood-Shalatter’s Disease can affect anyone during growth spurts, when bones, muscles and tendons are undergoing rapid changes. However, High Jump increases the risk for this condition as a result of the additional stress on the growth plates, tibia and patellar tendon.
Prevention: Avoiding sudden spikes in training load and ensuring adequate recovery between sessions is the most effective prevention tool. Gentle range-of-motion exercises and stretching to prevent stiffness may also be prescribed by a physiotherapist.
Treatment: Rest, ice and protection. A doctor will usually focus on reducing pain and swelling through prescribed rest, stretching and possibly anti-inflammatory medication. As it affects the growth plate, most symptoms will disappear when a child completes the adolescent growth spurt.
Plantar fascilitis
Description: The inflammation or damage to the plantar fascia, the fibrous band of tissue extending from the heel bone along the sole of the foot towards the toes.
Symptoms: Plantar fascilitis most commonly presents as pain under the heel or in the arch of the foot. Depending on the stage of injury, the pain is commonly greatest with the first steps and improves as the body warms up. Pain will usually return after exercise and be especially bad the morning after training.
Causes: Causes of plantar fascilitis can be divided into traction or compression injuries.
Traction plantar fascilitis is the most common amongst jumpers. Traction plantar fascilitis are caused by repeated overstretching of the plantar fascilitis. This can be caused by poor foot biomechanics or weakness of the foot arch muscles and exacerbated by footwear with poor support. Tight calf muscles or a stiff ankle increase the risk factor for developing plantar fascilitis.
Compression plantar fascilitis is caused by direct trauma to the plantar fascia.
Prevention: As foot biomechanics are the main predisposing factor for the injury, working with a biomechanist to correct the athlete’s running and jumping biomechanics may be an effective prevention for athletes with a history of the injury.
Keeping the High Jump area clear and ensuring appropriate footwear is worn can assist prevent compression plantar fascilitis.
Treatment: Rest, ice and protection. A doctor may recommend anti-inflammatory medication. A physiotherapist may develop a strength and flexibility program to strengthen foot arch muscles and improve range of motion. With early treatment, significant recovery is usually experienced within two months.
Medial Tibial Stress Syndrome (Shin Splints)
Description: Commonly referred to as ‘shin splints’ MTSS is an overuse injury that results in the inflammation of the muscles, tendons and bone tissue around the tibia (shinbone).
Symptoms: A pain experienced anywhere along the shinbone from the knee to the ankle. Pain generally develops gradually over several weeks and may be felt throughout and after any activity. Less frequently, swelling develops in the lower leg with small bumps along either side of the shin bone.
Causes: Overpronation during the High Jump runup and takeoff is believed to be a significant contributing factor to MTSS. This is where the athlete’s foot strike during the approach has an excessive flattening of the foot arch, resulting in the force not being evenly spread throughout the foot. This places increased pressure on the arch of the foot and greatly increases the stress placed on the lower leg.
Weakness or tightness in the posterior muscles may place excessive strain on the on the muscles in the front part of the lower leg.
Prevention: Developing calf and anterior tibial strength, flexibility and endurance can assist in preventing MTSS in conjunction with wearing appropriate footwear and avoiding rapid changes in training intensity.
Treatment: Rest, ice and protection. Lower limb impact should be reduced until inflammation has been removed. A physiotherapist may recommend light massage, myofascial release or deep tissue massage.
Patellofemoral Pain Syndrome
Description: The deterioration and softening of cartilage on the under surface of the knee cap. Jumpers are at significant risk of developing the injury due to the repeated stress experienced by the knee joints during the approach and takeoff action, especially if the athlete has an incorrect technique that exacerbates load on the knee.
Symptoms: Pain and tenderness over the patella tendon, exacerbated during activities that apply pressure to the knee joints (e.g. jumping and landing and feet). Onset of pain is normally gradual rather than traumatic. Another common symptom is a ‘grinding’ sensation when bending or extending the knee.
Causes: Runner’s knee occurs when the patella (kneecap) rubs against the femur (thigh bone), leading to deterioration of the patellofemoral joint. It commonly occurs as an overuse injury from repeated stresses to the knee but may also result from poor biomechanical control, weak hamstrings and quadriceps muscles or abnormal muscle imbalance between the adductors and abductors.
In some cases, patellofemoral pain syndrome is caused by misalignment of the knee due to a congenital condition. As highlighted in Section 3, it is important to have an athlete signed off by their Primary Care Physician prior to commencing regular Fosbury Flop training.
Prevention: Developing calf and anterior tibial strength, flexibility and endurance can assist in preventing MTSS in conjunction with wearing appropriate footwear and avoiding rapid changes in training intensity.
Treatment: Rest, ice and protection. The goal of treatment is to reduce pressure on the kneecap and joints. With enough rest, cartilage damage will often repair itself. In some cases, surgery may be required to correct misalignment of the knee, to release tension and allow for a greater range of movement.
Sprained Ankle
Description: An acute injury that results in the overstretchingor tearing of the ankle ligaments.
Symptoms: Depending on the severity of the sprain, a sprained ankle may result in mild pain during weight bearing exercises, or ongoing severe pain. A sprained ankle can affect the athlete’s balance, movement and in moderate and severe cases, result in severe swelling and stiffness.
Causes: Sprained ankles are an acute injury that result from a force being applied to the ankle joint, which causes an excessive range of movement. The biggest risk factor for a sprained ankle is having a previous ankle injury that has not fully recovered. Other causes include lack of ankle strength,lack of ankle flexibility and poor balance.
Prevention: Sports Medicine Australia recommend regular agility, flexibility, balance and strengthening exercises as the most effective method for avoiding sprained ankles. Athletes who have a history of sprained ankles should avoid returning to jumping until approved by a sports medicine expert and may benefit from ankle taping or bracing.
When performing the scissors, the appropriateness of the landing area must be considered by the coach. Surfaces that are uneven (including old/damaged high jump bags) must be avoided.
Treatment: Rest, ice and protection. A sports medicine professional should be seen as quickly as possible after the injury to determine the extent and tailor an appropriate treatment plan. Most sprained ankles heal within six weeks, but severe sprains can take as long as 12 weeks to recover. A physiotherapist can plan an effective High Jump specific rehabilitation program that strengthens the ankle to aid recovery and avoid reoccurrence of the injury. This is especially important for sprained ankles, as a previous sprain is the most significant risk factor of future injury.
Chronic Repetitive Flexion Injury of the Cervical Spine
Description: An overuse flexion or forward hinging injury of the cervical spine, noted to occur in High Jumpers with poor landing technique. The cervical spine is the topmost part of the spine, running alone the neck from the skull to the thoracic spine (upper back).
Symptoms: Athletes will experience pain in the neck,stiffness moving the head from side to side and occasionally neck spasms in more severe cases. Physicians will look for compression fractures or kyphotic angulation to confirm the diagnosis.
Causes: Incorrect landing technique that results in the athlete landing on their neck places high flexion loading on the cervical spine.
Prevention: Establishing correct landing technique from the athlete’s first introduction to the Fosbury Flop reduces the loading on the neck. Coaches must take action when they observe an athlete who continues to land on their neck to correct the issue. This may necessitate removing the bar until the athlete has perfected the desired landing position.
Treatment: All spinal issues should immediately be referred to a medical professional for diagnosis. Generally, return to sport will not be approved by physicians until the athlete is a symptomatic and full neck strength and function is restored.
Technical Skills to be Trained
The following activities should not be considered as a comprehensive description of all activities which should be undertaken to ensure that athletes are ready to perform the Flop high jump technique but provide a guide of the types of skills that athletes should practise to develop an efficient Fosbury Flop technique.
These skills should be combined with an age-appropriate strength and conditioning program designed by an expert Strength and Conditioning coach and tailored for the unique requirements and challenges of the High Jump.
Running on a Curve: The athlete should aim to run with an upright (vertical) posture while learning inwards. Gary Bourne states that running a curve on its own (without a jump) has a technical benefit for beginner athletes and physical conditioning benefit to beginner and experienced athletes.
Running Technique for the High Jump Approach: The coach should observe a taller body posture and higher knee lift than during top speed sprinting.
Rhythmical Accelerated Run-up: The athlete should demonstrate a gradual acceleration from the start of the run up, throughout the curve and all the wayto the touch down for take-off, reaching optimal speed for take-off at touch down.
Accurate J-Shaped Run-up: The athlete should develop a J-shaped run up that allows them to arrive at the correct take-off point consistently. The coach should ensure that the athlete does not step outside of the curve on the penultimate stride or inside of the curve on the final four strides prior to take-off by ‘steering’ towards the takeoff point. This can be most easily achieved by marking the curve on the ground with chalk or tape during training.
Required Lean-Away at Take Off: Successful Flop High Jumpers exhibit very little or no leaning back through the trunk at touchdown for take-off. However, they do exhibit a significant “lean-away” position (15 degrees and often more) that is acquired as a result of running fast on a curve. This lean-away (not lean-back) is what produces the necessary lowering of the centre of mass during the preparation for take-off. The reason for the upright trunk position at touchdown is that the Flop technique capitalises on “lean-away” gained from good curve running, along with the take-off foot out and across the body in front, during the eccentric phase of the take-off.
The horizontal and centrifugal braking that occurs at touchdown about the horizontal and sagittal axes of the jumper stretches the tendons and muscles involved in take-off while allowing the athlete to minimize their take-off time. This elastic energy is available immediately at the end of the eccentric phase for the rapid upward acceleration of the body. It is also supported to varying degrees by concentric contraction during the latter half of take-off time.
The take-away is that it is important to develop a technical model where the jumper arrives at the take-off with minimal or no leanback but a lean away of approximately 15 degrees.
Rotation: Ask the athlete to run five strides in a straight line, then plant the foot straight and drive their swing leg knee forcefully upward. At the same-time they should reach vertical upward with the arm on the swing leg side. Ask them to hold their landing position.
After landing ask them to note the direction of their hips and landing foot. They will have rotated in the air approximately 90 degrees. Point out to them that this rotation is a consequence of the angular momentum gained from the eccentric force generated during the take-off movements on one side of the body and then transferred to the whole body at take-off (the definition of an eccentric force is a force directed outside of the CM).
The rate of rotation (in individual cases) is a matter of manipulating the angular momentum of the body in flight, thus increasing or decreasing their angular velocity of the body (how fast and how far they will rotate) by raising the arm and maintaining a vertical posture – or not. Give the rotating ice skater or gymnast examples where distributing the mass of the body further than the axis of rotation slows the rate of rotation and bringing the mass closer speeds rotation up. Get them to try this several times, emphasising that it is not necessary to drive the knee across the body during take-off. Get them to try it while extending both arms outward (less rotation) or with an extended (straight) swing leg (much more rotation).
Raising the Centre of Mass at Take-off: Look for toe up, knee up and arm up and ensure that the centre of mass is above the take-off foot.
Knee Drive Speed: Look for a fast knee drive through the creation of a short lever of the swinging leg and a longer penultimate stride and shorter take-off stride. Ensure that the knee of the swinging leg is not trailing the hip at touchdown for take-off.
Clearance Position: Ask the athlete to drive the arm up or reach vertically during the take-off movement, then guide it along the bar during the early flight before reaching under the bar toward the lead leg foot during clearance. This reduces the moment of inertia of the body about its horizontal axis during clearance, increasing the rate of rotation about the bar at this point.
Avoid instructing young athletes to ‘arch’ over the bar as this will often lead to the athlete hyperextending their spine. This has the potential to cause damage to the spine over the long-term, especially when coaching young athletes.
Control of Rotation: Teach the athlete how to control their trunk and limbs to slowdown rotation on the way to peak height, increase the speed of rotation during bar clearance, then decrease the speed of rotation during the fall to the mats.
High Jump Equipment
Using appropriate equipment, ensuring that it is of asuitable condition and complying with all relevant EducationDepartment, Athletics Australia or IAAF recommendations isessential for avoiding injuries during High Jump.
Recommended High Jump Mat Dimensions:
IAAF Guidelines: The landing mat should not measure lessthan 6m x 4m, with a height of no less than 70cm with a covering of a spike proof protective mat.
Athletics Australia recommends that for secondary schools,the landing area should, where possible, be at least 6m x3m, and where athletes are jumping 1.50m or higher theminimum height of the mats should be at least 60cm (ifpossible, 70cm). The mats should have a protective wear pad,which covers any gaps between the units which make up thelanding area.
Flexi Bar: Using a Flexi Bar is an appropriate modification for developing athletes that avoids injuries that may occur when an athlete lands on a fibreglass bar. It is important that coaches ensure that when using a Flexi Bar that the uprights are secured sufficiently to ensure that they do not collapse inwards and fall on the athlete should they become entangled in the bar during their jump.
High Jump Spikes: Appropriate footwear contributes to avoidance of injury that may occur when an athlete slips during their approach. High Jump spikes differ from sprinting spikes in that they include spikes in the heel to offer additional grip and reduce the likelihood of loss of traction. This is especially important when planting the foot for take-off.
Video Equipment: The regular use of a video camera or mobile phone capable of slow-motion playback is important for providing accurate feedback on curve running, touchdown and take-off positions, and clearance position. Even the most experienced coach will be unable to see all the important information during the phases of the Fosbury Flop without the aid of video equipment, and recording is an essential tool for analysing the technique of a jumper. It also assists athletes’ own learning by giving them a visual understanding of what they did.
Triangular Bars: In no circumstances should triangular or square bars ever beused.
State Education Requirements
The following states have High Jump safety policies that must be followed when coaching in a school training or competition setting.
New South Wales
Department of Education Supervisor Requirements: The teacher/instructor must have appropriate expertise and or training in the teaching/ coaching in Athletics.
Fosbury Flop Requirements: Specially selected students who display promise in the lead-up activities should be chosen for development in small specialised groups conducted by teachers or coaches with specific expertise in the event.
Queensland
Education Queensland Supervisor Requirements: An adult with Level 2 Intermediate Club Coach accreditation.
Fosbury Flop Requirements: Fosbury flop high jump is unsuitable for class groups. Only students aged 10 and over may be engaged in Fosbury Flop High Jump. Students who show promise in lead up activities may be chosen for development in small, specialised groups.
Victoria:
Department of Education and Training Supervisor Requirements: High jumping should only be permitted where teachers or instructors are experienced inhigh jump instruction or have appropriate qualifications.
Fosbury Flop Requirements: The Fosbury Flop technique can be used if…the students have developed the necessary preliminary skills for the run up, take off , flight and landing phases of the jump.
Western Australia
Department of Education Supervisor Requirements: Supervising teachers should have had specific training in the use of the technique or should have a clear working knowledge of all aspects of the technique.
